// MaskSurface is a wrapper around cairo_mask_surface().
func (v *Context) MaskSurface(surface *Surface, surfaceX, surfaceY float64) {
C.cairo_mask_surface(v.native(), surface.native(), C.double(surfaceX),
C.double(surfaceY))
}
func (self *Surface) MaskSurface(surface *Surface, surface_x, surface_y float64) {
C.cairo_mask_surface(self.context, surface.surface, C.double(surface_x), C.double(surface_y))
}
//MaskSurface paints the current source using the alpha channel of surface
//as a mask.
//Opaque areas of surface are painted with the source, transparent areas are
//not painted.
//
//Originally cairo_mask_surface.
func (c *Context) MaskSurface(s Surface, offsetVector Point) *Context {
x, y := offsetVector.c()
C.cairo_mask_surface(c.c, s.XtensionRaw(), x, y)
return c
}